Relay mounting distortion elimination bracket



May 2, 1967 w. A. DEPNER RELAY MOUNTING DI$TORTION ELIMINATION BRACKETFiled May 26, 1965 INVENTOR WILLIA .DEPNER /;z% Z\ United States Patent3,317,868 RELAY MUUNTHNG DISTORTION ELIMINATION BRACKET William A.Depner, Napervillc, Ill., assignor to Automatic Electric Laboratories,Inc., Northlake, Ill., a corporation of Delaware Filed May 26, 1965,Ser. No. 458,967 4 Claims. (Cl. 335-132) This invention relates to themounting of relays and in particular to the mounting of telephone typerelays.

Presently telephone type relays are mounted directly by their L-shapedheelpieces to their respective base plates. This is accomplished bymeans of fastening screws which pass through apertures in the base plateand are received by threaded apertures in the shorter leg of theheelpiece. The fastening screws are tightened until the heelpiece isdrawn firmly against the base plate. However, since base plates andheelpieces are very often manufactured with minutely irregular surfaces,a mounted relay will not always fit flush against the base plate, andconsequently distortion will occur in the heelpiece.

The leg of the heelpiece not used in mounting the relay to the baseplate and which protrudes from the base plate, usually is long inrelation to the leg used to fasten the relay to the base plate. Themoving components of the relay are attached to this longer leg,therefore any distortion occurring at the fastened leg will be greatlymultiplied and magnified at the free end of the longer leg. For example,the armature of the relay is attached to the free end of the longer legof the heelpiece and makes contact with the free end of the core, thelatter ordinarily being mounted to the shorter leg of the heelpiece andrunning parallel to and in the same direction as the protruding leg ofthe heelpiece. When the coil of the relay is energized, the armature ispulled against the free end of the core, and simultaneously the armatureoperates contact springs which are also attached to the longer,protruding leg of the heelpiece. After the relay has been assembled, thearmature is precisely adjusted to obtain the correct air gap between thearmature and the free end of the core. If, at the time the relay issubsequently mounted, the heelpiece becomes distorted, for instancebecause of the aforementioned irregularity, there will be a change inthe physical relation of the core to the heelpiece, and thus a change inthe air gap. If this occurs, the stroke of the armature will bedifferent from what it was prior to the mounting, in which case thefunctioning of the associated contact springs will also be affected.Because of this distortion and the resultant change in relay adjustment,the operation of the relay will be adversely affected and its usefullife may be shortened. To remedy this, the relay user has to re-adjusteach relay subsequent to mounting. This is costly and it requires timewhich might be more usefully spent.

To substantially avoid the distortion causing these problems and thusnegate the need for re-adjustment of mounted relays the inventionproposes to mount the relay through the medium of a mounting bracketdesigned so as to absorb the mounting forces and thereby substantiallyeliminate distortions of the relay.

The bracket shown in the embodiments of the invention disclosed hereinis L-shaped, as is the heelpiece of the relay, and is made to fit overand conform to the contours of the heelpiece. The bracket as disclosedis attached to the heelpiece at two locations; to the longer leg of theheelpiece by means of the pile-up screws, and to the shorter leg bymeans of the core screw. However, the bracket may be attached to theheelpiece in other suitable ways if desired.

The bracket has a number of embossed portions on its 3,317,868 PatentedMay 2, 1967 shorter leg, and each embossed portion has a threadedaperture therethrough. These embossed portions are received by aperturesin the shorter leg of the heelpiece which are somewhat larger indiameter than the embossed portions so that there will be a loose fit,allowing the embossed portions to move within the apertures withouttransferring the movement to the heelpiece.

The relay is mounted to the base plate by means of fastening screwswhich pass through apertures in the base plate and fasten into thethreaded apertures in the embossed portions of the bracket; thus ifdistortion occurs it will be substantially absorbed by the bracket andnot transferred to the heelpiece.

Accordingly, it is an object of this invention to provide a means bywhich distortions due to the mounting of relays may be substantiallyeliminated.

Another object of this invention is to eliminate the need for having tore-adjust relays once they are mounted on their respective base plates.

A feature of this invention is the indirect manner in which a relay ismounted through the medium of a bracket, whereby the bracket absorbsmounting forces which may arise and which would, without the bracket, beabsorbed directly by the heelpiece.

Other objects and features of the invention will become more apparent byreference to the following description taken in conjunction with theaccompanying drawings of which:

FIG. 1 is an exploded perspective view of an embodiment of the relayassembly including a mounting bracket and associated cover according tothe invention. The figure shows how the bracket is to be used to mountthe relay to a base plate,

FIG. 2 is a side view of the relay of FIG. I mounted to its base plateby means of the mounting bracket, but with the cover removed.

FIG. 3 is a sectioned side view of the heelpiece of the relay of FIGS. 1and 2 and the mounting bracket, showing the embossed portion of thebracket and the manner in which the bracket overlies the heelpiece.

FIG. 4 is a perspective view of another embodiment of the mountingbracket according to the invention, to be used with a difierent type ofrelay whose heelpiece is shown.

FIG. 1 shows that mounting bracket 12 is fastened in an overlying mannerto heelpiece 11 of relay 10 by screws, such as 14 which pass throughapertures, such as 15, in spring pile-up 16, then through apertures,such as 17 in mounting bracket 12, and are finally received by threadedapertures, such as 18, in heelpiece 11. Screws, such as 14, also serveto fasten spring pile-up 16 to heelpiece 11. Mounting bracket 12 is alsofastened to heelpiece 11 by screw 19 which passes through aperture 20 inmounting bracket 12 and into threaded aperture 21 in core 22 (shown inFIG. 2) which carries coil 43 of relay 10. Screw 19 simultaneouslyfastens core 22 and associated coil 43 of relay 10 to heelpiece 11.

Relay 10 is mounted to base plate 13 indirectly by means of mountingbracket 12 at a point intermediate the points of attachment of mountingbracket 12 to heelpiece 11. Screws, such as 23, pass through apertures,such as 24, in base plate 13 and are received by threaded apertures,such as 41, in embossed portions, such as 25 (shown in FIG. 3). Byindirectly mounting relay 10 to base plate 13 through the medium ofmounting bracket 12, distortions which may occur in the mounting aretransferred to mounting bracket 12 and not to heelpiece 11.Consequently, re-adjustment of relay 10, once mounted, will not benecessary.

Cover 26, made from a transparent plastic, as shown, but which may beconstructed from any suitable material,

slides onto mounting bracket 12 by means of cut-outs 27 on the inside ofcover 26, and along sides 28 of mounting bracket 12. When apertures 29in cover 26 reach projections 30 on mounting bracket 12, cover 26 snapsonto mounting bracket 12. Cover 26 is provided to prevent damage tospring pile-up 16 due to the handling of relay 10, and cover 26 also maybe used once relay is mounted to base plate 13 to prevent dust fromsettling on contacts 31 of spring pile-up 16.

FIG. 2 shows an assembled side view of relay 10 of FIG. 1 mounted tobase plate 13 through the medium of mounting bracket 12. It can be seenthat when screws 23 are tightened, mounting bracket 12 and base plate 13are pressed together. Any irregularities in the surfaces will tend todistort mounting bracket 12, but since mounting bracket 12 isindependent of heelpiece 11 of relay 10 at the point of mountingvirtually all of the forces tending to cause distortion will be absorbedby mounting bracket 12 and consequently not be transferred to heelpiece11. If mounting bracket 12 were not used, heelpiece 11 and base plate 13would be pressed together when screws, such as 23, were tightened.Heelpiece 11 would then absorb the distortion and in doing so wouldchange the pre-adjusted relationship between armature 32 and core 22,thus changing stroke 223 of relay 10. If stroke 223 of relay 10 ischanged, armature arm 224 will operate the springs 216 irregularly andrelay 10 will have to be readjusted. Thus thorugh the medium of mountingbracket 12, a need for re-adjustment of relay 10, once mounted, isavoided. This in turn not only saves time but money as well.

FIG. 3 shows mounting bracket bracket 12 in position overlying heelpiece11. In this view it can be seen that mounting bracket 12 has an embossedportion which extends into aperture 340 in heelpiece 11. Aperture 340 islarge enough to allow embossed portion 25 to move within aperture 340when fastening screws are tightened into threaded aperture 41 inembossed portion 25. Thus distortions occurring in mounting bracket 12due to mounting are not transferred to heelpiece 11.

FIG. 4 shows a heelpiece 411 of a different type of relay, called theClass C Relay, shown in Automatic Electric Tech. Bulletin 537, RelaysClass B and C, page 6, and its mounting bracket 412. Mounting bracket412 is used in a similar manner as mounting bracket 12 in FIG. 1, as itprovides substantial distortion elimination due to mounting.

It will be obvious to those skilled in the art that changes andmodifications may be made without departing from this invention in itsbroadest aspects and therefore the aim in the appended claims is tocover all such changes and modifications as in the true spirit and scopeof this invention.

What is claimed is:

1. An arrangement for mounting a relay to a base plate, said relaycomprising an L-shaped heelpiece having a first and second leg, a core,a screw mounting said core to said first leg, said first leg includingtherein at least one hole having a predetermined diameter, said coreextending in the same direction and parallel to said second leg, aspring pile-up, and screws attaching said spring pileup to said secondleg, said arrangement comprising: an L-shaped bracket having first andsecond legs, the first leg of said bracket including at least oneembossed portion with a threaded aperture, said portion having anoutside diameter sufficiently smaller than said predetermined diameterof said one hole so as to clear said heelpiece, the two legs of saidL-shaped bracket being attached to the two legs of said heelpiece bysaid core screw and said pile-up screws, respectively, so that the legsof said bracket overlies the corresponding legs of said heelpiece withsaid one embossed portion being received in said one hole in saidheelpiece, and at least one fastening screw for securing said bracket tosaid base plate, said fastening screw received in the threaded aperturein said one embossed portion, whereby said relay is mounted to said baseplate substantially without transferring mechanical distortions to saidrelay, through the medium of said bracket.

2. An arrangement for mounting a relay to a base plate as claimed inclaim 1, wherein said one hole in the heelpiece is located intermediatesaid core screw and said pile-up screws, and wherein the second leg ofsaid bracket includes, slidably attached thereto, a cover for protectingsaid spring pile-up.

3. An arrangement for mounting a relay to a base plate, said relaycomprising an L-shaped heelpiece having a first and second leg, a coreand a coil thereon, a screw mounting said core to said first leg, saidfirst leg including therein at least one hole having a predetermineddiameter, said core extending in the same direction and parallel to saidsecond leg, a spring pile-up, screws attaching said spring pile-up tosaid second leg, and an armature attached to the free end of said secondleg so that upon energization of said coil said armature will bemagnetically attracted to said core, said arrangement comprising: anL-shaped bracket having first and second legs, the first leg of saidbracket including at least one embossed portion with a threadedaperture, said portion having an outside diameter sufficiently smallerthan said predetermined diameter of said one hole so as to clear saidheelpiece, the two legs of said L-shaped bracket being attached to thetwo legs of said heelpiece by said core screw and said pile-up screws,respectively, so that the legs of said bracket overlies thecorresponding legs of said heelpiece with said one embossed portionbeing received in said one hole in said heelpiece, a cover attached tosaid second leg of said bracket for protecting said spring pile-up, andat least one fastening screw for securing said bracket to said baseplate, said fastening screw received in the threaded aperture in saidone embossed portion, whereby distortion of said heelpiece and core, andresultant changes in the adjustment of said relay are minimized.

4. A bracket for the mounting of a relay to a base plate by means of atleast one fastening screw, said relay being of the type comprising anL-shaped heelpiece having a first and second leg, said first leg havingat least one aperture therethrough, said aperture having a predetermineddiameter, said bracket being L-shaped and having a first and second legwith means for attaching said bracket to said heelpiece in an overlyingrelationship, said first leg of said bracket having at least oneembossed portion to be received by said one aperture in said first legof said heelpiece, said embossed portion having an outside diametersufiiciently smaller than said predetermined diameter of said oneaperture so as to clear said heelpiece, and said embossed portion havinga threaded aperture therethrough for receiving said one fastening screw,whereby said relay may be mounted to said base plate, substantiallywithout transferring mechanical distortions to said relay, through themedium of said bracket.

References Cited by the Examiner UNITED STATES PATENTS 592,432 10/1897MoBerty 335-128 1,185,369 5/1916 Cook 335-128 BERNARD A. GILHEANY,Primary Examiner.

R. N. ENVALL, 1a., Assistant Examiner.

4. A BRACKET FOR THE MOUNTING OF A RELAY TO A BASE PLATE BY MEANS OF AT LEAST ONE FASTENING SCREW, SAID RELAY BEING OF THE TYPE COMPRISING AN L-SHAPED HEELPIECE HAVING A FIRST AND SECOND LEG, SAID FIRST LEG HAVING AT LEAST ONE APERTURE THERETHROUGH, SAID APERTURE HAVING A PREDETERMINED DIAMETER, SAID BRACKET BEING L-SHAPED AND HAVING A FIRST AND SECOND LEG WITH MEANS FOR ATTACHING SAID BRACKET TO SAID HEELPIECE IN AN OVERLYING RELATIONSHIP, SAID FIRST LEG OF SAID BRACKET HAVING AT LEAST ONE EMBOSSED PORTION TO BE RECEIVED BY SAID ONE APERTURE IN SAID FIRST LEG OF SAID HEELPIECE, SAID EMBOSSED PORTION HAVING AN OUTSIDE DIAMETER SUFFICIENTLY SMALLER THAN SAID PREDETERMINED DIAMETER OF SAID ONE APERTURE SO AS TO CLEAR SAID HEELPIECE, AND SAID EMBOSSED PORTION HAVING A THREADED APERTURE THERETHROUGH FOR RECEIVING SAID ONE FASTENING SCREW, WHEREBY SAID RELAY MAY BE MOUNTED TO SAID BASE PLATE, SUBSTANTIALLY WITHOUT TRANSFERRING MECHANICAL DISTORTIONS TO SAID RELAY, THROUGH THE MEDIUM OF SAID BRACKET. 